Drum reconditioning process

ABSTRACT

A drum reconditioning method including the steps of removing a double seamed closure from a drum body side wall by wedging the closure flange structure to an acute angle with respect to the drum body, rotating the drum and cutting the portion of the closure flange that bridges the drum body flange, removing the closure and treating the interior of the drum body, and double seaming a new closure to the treated drum body.

United States Patent [191 Rosenbloom [451 May 22, 1973 [54] DRUMRECONDITIONING PROCESS [75] Inventor:

[73] Assignee: Doric Corporation, Oklahoma City,

Okla.

Morris Rosenbloom, Chicago, Ill.

J Z Z7- 7 2,845,887 8/1958 Kradoska ..l13/1 K 2,943,386 7/1960 Katz ..113/1 K 3,083,455 4/1963 Marden ..30/9

Primary Examiner-Richard J. Herbst AttorneyMax Dressler et al.

[57] ABSTRACT A drum reconditioning method including the steps ofremoving a double seamed closure from a drum body side wall by wedgingthe closure flange structure to an acute angle with respect to the drumbody, rotating the drum and cutting the portion of the closure flangethat bridges the drum body. flange, removing the closure and treatingthe interior of the drum body, and double seaming a new closure to thetreated drum body.

10 Claims, 5 Drawing Figures PATENTEU I 3, 734, 043

DRUM RECONDITIONING PROCESS BACKGROUND OF THE INVENTION The presentinvention relates in general to the reconditioning of large drums thatare commonly used to ship fluids, such as petroleum products, chemicals,solvents, paints, adhesives, etc. Such drums conventionally include ahollow, generally cylindrically shaped body that is closed at both endsby a closure or head which is permanently secured to the body by adouble seam configuration. Access to the interior of such drums forfilling and discharge is attained through a bung hole that is commonlyprovided in the side wall of the drum, or in one of the ends thereof.Tight head drums of the above described type come in different sizes,but a common size is a 55 gallon drum, and it will be understood thatdrums of this size are relatively expensive. Hence, it has been commonpractice to reuse such drums to avoid the expense attendant to disposingof a drum after only a single use.

Since many of the products that are shipped within drums of the abovedescribed type leave a residue in the drum after it has been emptied, itis necessary to treat the interior of the drum after it has been emptiedto remove the residue and place the drum in a condition suitable for usewith a different product. The bung hole access opening does not providesufficient clearance to enable a thorough interior cleaning operation tobe performed, and hence those concerned with the reconditioning of tighthead drums have resorted to several expedients in gaining access to adrum for reconditioning purposes.

The first, and most common, expedient that is practiced in the art is toconvert a tight head drum to an open head drum by cutting into the sidewall of the drum body beneath the closure lock seam. This provided readyaccess to the interior of the drum, but an open head drum is notcompletely satisfactory for all products, and hence the need remains fortight head drums.

In view of the continuing need for tight head drums, those skilled inthe art have resorted to a technique which is commonly referred to asreheading or remanufacturing. The first reheading approach was to severthe drum body wall beneath the double seam and to double seam a newclosure onto the body wall in the same manner as the original closure,after the interior of the drum had been treated. However, since the sidewall of the drum was severed with this approach, such reheaded drums hada reduced volumetric capacity. It was a common experience for 55 gallondrums reheaded in this manner to lose as much as l k 2 gallons ofcapacity in each reheading operation, and such drums also were not ofequal height.

In view of the objection to loss of capacity and nonuniformity of drumsize, those skilled in the art have long sought a satisfactory reheadingmethod that would obviate these problems. It has been proposed (see forexample Kradoska US. Pat. No. 2,845,887) to completely remove the headof a drum without cutting by unfolding the conventional double seamclosure. This expedient has not been practiced commercially, because theequipment that is necessary to completely remove a lock seam closure inthis fashion is prohibitively expensive.

A further reheading process that has been proposed is to partiallyunfold the double seam of the closure at the bottom of a drum, sever theflange on the side wall of the drum body, and weld the closure back tothe drum body side wall after the interior thereof has been treated.Such a process is disclosed, for example, in Katz US. Pat. No.2,943,386. This process obviates the problem of loss of capacity, and atthe same time insures that the reconditioned drums will be of the samesize as original drums. However, drums having covers welded theretocannot be repeatedly reconditioned, so that this expedient is limited.

SUMMARY OF THE INVENTION The present invention solves the problems ofthe prior art by providing a process whereby drums may be reconditionedby cutting a portion of the double seam of the closure while retainingthe flange on the body wall of the drum intact. This enables a newclosure to be double seamed onto the drum body in a conventional mannerafter the interior of the drum has been treated, so that thereconditioned drum has the same capacity and height as the originaldrum. An end of the reconditioned drum can be removed again and again,and the drum reused with different products, so that the process of thepresent invention has great economic advantages over prior artprocesses. While the present invention requires the use of a newclosure, the advantages of the invention far outweigh this increase incost.

In its broadest sense, the present invention contemplates the severingof the portion of the closure that bridges the flanges of the closurewhich embrace the flange on the body of the drum by effecting relativerotary motion between the drum and a cutting tool that is fed undercontrol and observation into progressive engagement with the closurestructure. The closure flange structure is initially partially unfoldedto a position disposed at an acute angle with respect to the body wallof the drum, to accurately locate the closure flange relative to thecutting tool, and to enable ready separation of the closure from thedrum body once the severing step is completed. It will be understoodthat by only partially folding the closure flange structure relative tothe drum body, the closure is not excessively fatigued.

The present invention also provides a means whereby the drum canaccurately be positioned relative to the flange unfolding tool and theclosure cutting tool. This is a problem of no small importance inremoving the head of a large shipping drum, since relatively widetolerances are accepted in the drum industry making various drumssupposedly of the same size different from one another. For example, ina drum head having a 22 2% inch inside diameter, tolerances of plus orminus one-sixteenth inch are tolerated, so that it is possible for drumsof this size to have an overall diametric variance of one-eighth inch.To solve problems resulting from attempting to remove heads from drumsof varying diameter, the present invention incorporates the step ofaccurately locating a drum relative to the drum removal means. In thisregard, a tapered centering member is provided in fixed spatialrelationship with respect to the flange unfolding mechanism and theflange severing mechanism, and relative movement is effected betweenadrum supporting platform and the centering member to cause the centeringmember to engage within the drum head and thereby accurately locate thedrum relative to the head removal means.

In accordance with another aspect of the invention, the flange severingmeans is adjustably located at an operator station, so that the positionthereof can be accurately manually controlled to insure that the cuttingmeans does not engage the flange on the body of the drum. To this end,both the cutting tool and the closure of the drum are readily visible atthe operator station, and a means is provided whereby the relationshipof the cutting means to the closure flange can be varied, when desiredor necessary. The presentinvention contemplates that the cutting meanswill progressively shear the bridging portion of the closure flange thatis wrapped around the end of the body flange, and since the body flangeis normally spaced from the bridging portion of the closure flange, theoperator can visually determine when the cutting operation has beencompleted.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view of adrum in position at an operating station of an exemplary form ofapparatus that may be used to remove the head from the drum;

FIG. 2 is an enlarged cross-sectional view through the upper portion ofthe drum of FIG. 1;

FIG. 3 is a view similar to FIG. 2, but showing the flange of the drumin a partially unfolded position;

FIG. 4 is a view similar to FIGS. 2 and 3 and showing in full lines aflange cutting member at the beginning of a flange cutting operation andin broken lines the position of the flange cutting member at the end ofthe flange cutting operations; and

FIG. 5 is a view similar to FIGS. 2-4 and showing the closure removalstep of the process of the present invention. I

DESCRIPTION OF THE PREFERRED EMBODIMENT While this invention issusceptible of embodiment in many different forms, there is shown in thedrawings and will herein be described in detail a preferred embodimentof the invention, with the understanding that the present disclosure isto be considered as an exemplification of the principles of theinvention and is not intended to limit the invention to the embodimentillustrated. The scope of the invention will be pointed out in theappended claims.

Referring first to FIG. 1, a closed end drum is illustrated in itsentirety at 10, and drum includes a generally cylindrical side wall 11that is sealed at one end by a closure 12. Closure 12 is double seamedto the body wall 11 in the usual manner, and it will be appreciated thata closure 12 may be provided at each end of the drum 10, or the end ofthe drum opposite the closure 12 may be permanently sealed in adifferent fashion. A bung hole opening 13 is illustrated in FIG. 1 inthe side wall 11 of drum 10, for filling and dispensing of products, andit will be understood that a similar bung hole opening may also beprovided in closure 16.

Referring now to FIG. 2, body wall 11 includes a reversely bend flange14 at one end thereof, and flange 14 is connected to body wall 11 by abridging portion 15. Drum portions 14 and 15, of course, extendcircumferentially around the end of the body wall 11 and flange portion14 is generally parallel with side wall 11. Closure 16 includes a mainhead portion 16 recesses inwardly from the end of body wall 11; a firstflange 17 extending outwardly from head portion 16 generally parallelwith body wall 11 and engaging the interior thereof; a second flange 18reversely bent with respect to flange 17, generally parallel with bodywall 11, and engaging the outer surface of body flange 14; and a thirdflange 19 generally parallel with body wall 1 1, reversely bent withrespect to flange 18, and interposed between body flange l4 and the endof wall 11 and in face-to-face engagement therewith. Flanges 17-19, ofcourse, extend circumferentially around the end of wall 11, and flanges17 and 18 are joined by bridging portion 20, while flanges 18 and 19 arejoined by bridging portion 21. The flanges on the closure 12 and bodywall 11 cooperate to form a conventional double seam, as will be wellunderstood to those skilled in the art. In forming such a seam inrelatively heavy gauge material that is utilized in drums of the typewith which the present invention is concerned, when the double seam isformed, a gap 22 exists between the end of body flange 14 and thebridging portion 21 between closure flanges 18 and 19. The presentinvention takes advantage of this clearance opening, which isapproximately onesixteenth inch in 18 gauge material (0.047 inch)commonly used in drums of the type described herein, by severing theclosure at this juncture, as is shown in F IG. 4 and as will behereinafter described.

The method of the present invention will be best understood by referringbriefly to an exemplary form of apparatus that may be utilized toperform the various steps of the invention. Such apparatus is showngenerally at 30 in FIG. 1, and includes side members 31 and 32 spannedby a top member 33 and a base 34. A drum supporting platform 35 isprovided at an operator station associated with apparatus 30, and in theillustrated embodiment, platform 35 is arranged for vertical movementrelative to the frame structure by a pneumatic cylinder 36 carried bybase 34. Platform 35 may be supported upon a carrier member 37, withbearing means 38 being provided between platform 35 and carrier member37, so as to enable platform 35 to rotate relative to carrier member 37.Carrier member 37 may be held against rotation by having end portions37A and 37B thereof engage within guide members 38 and 39 on framemembers 31 and 32, respectively, it being understood that guide members38 and 39 are arranged so as to guide the carrier member 37 and platform35 during vertical movement thereof by cylinder 36.

Because of the relatively wide tolerance that is accepted in the drumindustry, in order to insure that the drum 10 is accurately centeredwith respect to the apparatus 30, a tapered centering member 40 isrotatably supported upon cross member 33 above platform 35. Locatingmember 40 has a first small diameter portion 41 (FIG. 3) that is smallerin diameter than the internal diameter of flange 17 of closure 12, and asecond large diameter portion 42 that is larger in diameter than theinner diameter of flange portion 17 of closure 12. In this manner, whenthe drum 10 is moved upwardly by cylinder 36, the portion of centeringmember 40 between ends 41 and 42 will engage within the closure 12 andpositively center the drum on the apparatus 30.

In the performance of the process of the present invention, rotarymotion is imparted to drum 10, and the centering member 40 may beutilized to perform this step. In this regard, the centering member 40is preferably a hardened metal member which is provided with a knurledor serrated outer surface 43, so that when the cylinder 36 moves thedrum 10 into engagement with the centering member, the drum will bedriven thereby.

Member 40 may be rotated by a motor 44 carried by frame member 33 andcoupled to a shaft 45 on the member 40 through a gear box 46.

Summarizing briefly, the drum is initially loaded upon platform 35,which is initially spaced vertically below centering member 40. Cylinder36 is then energized in a conventional manner to move carrier member 37and platform 35 vertically upwardly until positive driving engagement isestablished between centering member 40 and closure 12. It will beunderstood that when the centering member 40 engages within closure 12,the drum 10 is accurately located relative to the frame of the machine.Motor 44 is then energized to impart rotary motion to drum 10, andbearing 38 enables platform 35 to rotate relative to carrier member 37which is constrained against rotation by guide members 38 and 39.

The next step of the process of the present invention is to partiallyunfold the double seam flange configuration of the drum from theposition of FIG. 2 to the position of FIG. 3. To achieve this, a wedgingmember 50 is provided which has a frusto-conically shaped externalsurface 52 that is disposed at an acute angle with respect to body wall11. Member 52 is carried by a shaft 53, which may be driven by a motor,not shown, although to perform the method of the present invention it isnot necessary that the member 52 be driven. Shaft 53 is supported withina housing 54, and housing 54 is mounted for vertical movement relativeto apparatus 30 by guide surfaces 55 on frame member 31. While anysuitable means may be provided for moving housing 54, a lead screw 56 isillustrated in FIG. 1, with one end of the lead screw being rotated by amotor 57, and with the other end of the lead screw being rotatablysupported in frame member 33. It will be appreciated that when motor 57is energized, lead screw 56 engages an internally threaded hole withinhousing 54 to vary the position of the wedging member relative to theclosure 12 on drum 10. The movement of wedging member 50 need not bemotorized, and can be done manually, but many event, wedging member 50is mounted in fixed relationship with respect to centering member 40, sothat when the wedging member is moved into engagement with the flangestructure of closure 12 as the drum 10 is rotated, the flange structurewill be accurately moved to the position of FIG. 3.

The relationship of the flange structure illustrated in FIG. 3 isimportant to the performance of the process of the present invention,since by folding the flange structure to an angle less than 90 withrespect to the wall 1 1 of the drum, severe stresses are not imparted tothe bridging portions and of the drum wall and closure, respectively. Inthe present invention, it is contemplated that drums will be capable ofbeing repeatively reconditioned, and it is desirable, to the extentpossible, to minimize flexure of the flange structure which ultimatelyresults in fatiguing of metal.

After the flange structure has been wedged, or partially unfolded to theposition of FIG. 3, a cutting member 60 is actuated under manual controlto sever the bridging portion 21 and thereby free closure 12 from thebody of the drum 10. While the flange unfolding and cutting steps may beperformed on the same machine and at the same work station, as shown inFIG. 1, it should be understood that this is not critical to the presentinvention, and these operations could be performed at different workstations by different pieces of equipment.

In FIG. 4, cutting tool is illustrated as including a cutting member 61secured to a holder 62 by a set screw 63, although it should beunderstood that the present invention contemplates that any suitabletype of cutting tool may be provided. Cutting tool 60 is mounted forvertical movement relative to apparatus 30 by suitable guide surfaces 64on frame member 32 and a lead screw 65 is illustrated in FIG. 1 formoving cutting tool 60. One end of lead screw 65 is rotatably supportedin frame member 30, while the opposite end of lead screw 65 is drivenunder manual control either by a motor 66, or directly by hand. Leadscrew 65 is positioned within an internally threaded hole within cuttingtool 60, so that when the lead screw is rotated the cutting tool ismoved vertically relative to the drum 10, it being understood that thecutting tool 60 moves along a path that is fixed spatially relative tocentering member 40.

After cutting tool 60 is moved vertically upwardly from the full lineposition to the broken line position shown in FIG. 4, the cutting member61 progressively severs the corner of bridging portion 21. Therelationship between the position of centering member 40, wedging member50 and cutting tool 60 is selected so that the edge of cutting member 61passes through the center of the gap 22 at the end of body flange 14.Means, not shown, may be provided for adjusting wedging member 50 andcutting tool 60 radially to accommodate different size drums.

As previously noted, it is desirable that the cutting member 61progressively move through the bridging portion 21 of the closure seam.In accordance with the present invention, the drum 10 is rotated througha plurality of revolutions as the cutting tool 60 is moved along itsbroken line cutting path illustrated in FIG. 4. This not only reducescutting effort, but also insures that if a flange of the drum has beenbent during use so that the edge of flange 14 is not precisely locatedrelative to the cutting member 61, the operator can readily vary theposition of the cutting tool, as desired. The cutting tool 60 may beadvanced to cut off both thicknesses of material on opposite sides ofgap 22, as shown in FIG. 5, or only the lower thickness of material maybe severed. In either event, once the platform 35 has been lowered towithdraw the centering member 40, the closure 12 can be readily removed.It should be noted that, with reference to FIG. 5, the internal diameterof the severed flange 19 is larger than the circumferential ribs thatare conventionally provided on the drum side wall, so that the flange 19can be readily removed from the drum.

Once the closure 12 has been removed from the drum side wall, theinterior of the drum may be treated in a suitable manner to removewhatever residue is present therein from the previously shippedmaterial. The treatment of the interior of the drum 10 may take the formof initially burning off any material therein, and subsequently shotblasting the charred remains of the residue. The interior of the drummay then be subjected to chemical baths, dried, painted and/or lined. Ifthe side wall 11 of the drum has been bent during previous use, the drummay be expanded to its original configuration prior to the performanceof the last steps. Once the drum has been restored to a conditionsuitable for reuse, a new closure is secured to the open end of the drumin the conventional manner to form a double seam with the pre-existingflange 14 on the side wall of the drum body.

From the foregoing it will be recognized that the process of the presentinvention enables a drum head to be removed without damage ordestruction to the flange on the drum side wall, so that when a new headis double seamed to the drum body, the reconditioned drum has the samecapacity and height as the original drum.

What is claimed is:

1. A method of reconditioning a normally closed generally cylindricaldrum having a hollow body wall and a closure sealed to said wall atleast at one end of said drum; said wall including a reversely bentflange at said one end which extends circumferentially around said wallin parallelism therewith; said closure including a main head portionpositioned interiorly of said body wall at said one end and first,second, and third flanges extending circumferentially around said wallin parallelism with said body wall andtin sealed relationship therewith,said first flange merging with said main body portion and engaging theinner surface of said body wall at said one end, said second flangemerging with said first flange and being reversely bent relative theretoand engaging the outer surface at said body wall flange, and said thirdflange merging with said second flange and being reversely bent relativethereto and positioned between said body wall flange and the outersurface of said one end of said body wall, said method comprising:rotating said drum about the axis of said body wall; forcing a wedgingtool into a flange folding position between the outer surface of saidbody wall and the third flange of said closure; retaining said wedgingtool in said flange folding position during rotation of said drum tofold the second and third flanges of the closure and the body flange toa position at an acute angle with respect to said body wall; moving acutting tool relative to said drum into a flange severing position inengagement with the portion of said closure bridging said second andthird flanges; progressively moving said cutting tool relative to saidbridging portion during rotation of said drum to sever said third flangefrom said closure while said body flange remains completely intact;removing said closure from said one end of said body wall to provideaccess to the interior thereof; treating the interior of said drum;placing a new closure on the open end of said body wall; and foldingfirst, second and third flanges on said new closure into the previouslydescribed sealed relationship with said body wall and flange thereof tothereby provide a reconditioned drum having the same height andvolumetric capacity as the original drum and which is itself capable ofbeing further reconditioned.

2. A method as set forth in claim 1 in which the main head portion ofsaid closure is recessed inwardly of the end of said body wall, andincluding the further step of inserting a tapered centering member intosaid closure to locate said drum relative to said wedging tool and saidcutting tool.

3. A method as set forth in claim 2 wherein said drum rotating step isperformed by positively holding said drum against said centering member,and rotating said centering member,

4. A method as set forth in claim 3 in which said drum is rotated abouta vertical axis, and wherein said holding step is performed by moving adrum supporting platform upwardly relative to said centering member.

5. A method as set forth in claim 1 wherein said drum is rotated severalrevolutions as said cutting tool is pro gressively moved relative tosaid bridging portion.

6. A method as set forth in claim 5 including the initial step oflocating the drum at an operator station where the cutting tool andclosure are readily visible, and including the further step of manuallycontrolling the progressive movement of said cutting tool to insure thatthe cutting tool does not engage the body flange.

7. A method of reconditioning a normally closed generally cylindricaldrum having a hollow body wall and a closure sealed to said wall atleast at one end of said drum; said wall including a reversely bentflange at said one end which extends circumferentially around said wallin parallelism therewith; said closure including a main head portionrecessed inwardly of said body wall at said one end and first, second,and third flanges extending circumferentially around said wall inparallelism with said body wall and in sealed relationship therewith,said first flange merging with said main body portion and engaging theinner surface of said body wall at said one end, said second flangemerging with said first flange and being reversely bent relative theretoand engaging the outer surface at said body wall flange, and said thirdflange merging with said second flange and being reversely bent relativethereto and positioned between said body wall flange and the outersurface of said one end of said body wall, said body flange terminatingshort of the closure portion which bridges said second and third flangesto provide a gap therebetween which extends circumferentially aroundsaid body wall, said method comprising: placing said drum on asupporting platform at an operator station in spaced relationship withrespect to a tapered centering member having a first portion with anexternal diameter smaller than the internal diameter of the first flangeof said closure and a second portion with an external diameter largerthan the internal diameter of the first flange of said closure;effecting relative movement between said platform and said centeringmember to cause said centering member to engage within said closure andcenter said drum at said operator station and to place said drum in alocation where said closure is readily visible; rotating said drum aboutthe axis of said body wall; forcing a wedging tool into a flange foldingposition between the outer surface of said body wall and the thirdflange of said closure; retaining said wedging tool in said flangefolding position during rotation of said drum to fold the second andthird flanges of the closure and the body flange to a position at anacute angle with respect to said body wall; moving a cutting toolrelative to said drum into a flange severing position in engage mentwith the portion of said closure bridging said second and third flanges;progressively moving said cutting tool relative to said bridging portionunder manual control during rotation of said drum while observing saidclosure to cause said cutting tool to enter the gap between said bodyflange and bridging portion to thereby sever said third flanges fromsaid closure while said body flange remains completely intact; effectingrelative movement between said platform means and said centering memberand removing said drum from said operator station; removing said closurefrom said one end of said body wall to provide access'to the interiorthereof; treating the interior of said drum; placing a new closure onthe open end of said body wall; and folding first, second and thirdflanges on said new clo- 9. A method as set forth in claim 8 whereinsaid centering member is positioned above said platform, and whereinsaid platform is moved vertically relative to said centering member.

10. A method as set forth in claim 9 wherein said drum rotating step isperformed by rotating said centering member while said drum is heldthereagainst by said platform.

1. A method of reconditioning a normally closed generally cylindricaldrum having a hollow body wall and a closure sealed to said wall atleast at one end of said drum; said wall including a reversely bentflange at said one end which extends circumferentially around said wallin parallelism therewith; said closure including a main head portionpositioned interiorly of said body wall at said one end and first,second, and third flanges extending circumferentially around said wallin parallelism with said body wall and in sealed relationship therewith,said first flange merging with said main body portion and engaging theinner surface of said body wall at said one end, said second flangemerging with said first flange and being reversely bent relative theretoand engaging the outer surface at said body wall flange, and said thirdflange merging with said second flange and being reversely bent relativethereto and positioned between said body wall flange and the outersurface of said one end of said body wall, said method comprising:rotating said drum about the axis of said body wall; forcing a wedgingtool into a flange folding position between the outer surface of saidbody wall and the third flange of said closure; retaining said wedgingtool in said flange folding position during rotation of said drum tofold the second and third flanges of the closure and the body flange toa position at an acute angle with respect to said body wall; moving acutting tool relative to said drum into a flange severing position inengagement with the portion of said closure bridging said second andthird flanges; progressively moving said cutting tool relative to saidbridging portion during rotation of said drum to sever said third flangefrom said closure while said body flange remains completely intact;removing said closure from said one end of said body wall to prOvideaccess to the interior thereof; treating the interior of said drum;placing a new closure on the open end of said body wall; and foldingfirst, second and third flanges on said new closure into the previouslydescribed sealed relationship with said body wall and flange thereof tothereby provide a reconditioned drum having the same height andvolumetric capacity as the original drum and which is itself capable ofbeing further reconditioned.
 2. A method as set forth in claim 1 inwhich the main head portion of said closure is recessed inwardly of theend of said body wall, and including the further step of inserting atapered centering member into said closure to locate said drum relativeto said wedging tool and said cutting tool.
 3. A method as set forth inclaim 2 wherein said drum rotating step is performed by positivelyholding said drum against said centering member, and rotating saidcentering member.
 4. A method as set forth in claim 3 in which said drumis rotated about a vertical axis, and wherein said holding step isperformed by moving a drum supporting platform upwardly relative to saidcentering member.
 5. A method as set forth in claim 1 wherein said drumis rotated several revolutions as said cutting tool is progressivelymoved relative to said bridging portion.
 6. A method as set forth inclaim 5 including the initial step of locating the drum at an operatorstation where the cutting tool and closure are readily visible, andincluding the further step of manually controlling the progressivemovement of said cutting tool to insure that the cutting tool does notengage the body flange.
 7. A method of reconditioning a normally closedgenerally cylindrical drum having a hollow body wall and a closuresealed to said wall at least at one end of said drum; said wallincluding a reversely bent flange at said one end which extendscircumferentially around said wall in parallelism therewith; saidclosure including a main head portion recessed inwardly of said bodywall at said one end and first, second, and third flanges extendingcircumferentially around said wall in parallelism with said body walland in sealed relationship therewith, said first flange merging withsaid main body portion and engaging the inner surface of said body wallat said one end, said second flange merging with said first flange andbeing reversely bent relative thereto and engaging the outer surface atsaid body wall flange, and said third flange merging with said secondflange and being reversely bent relative thereto and positioned betweensaid body wall flange and the outer surface of said one end of said bodywall, said body flange terminating short of the closure portion whichbridges said second and third flanges to provide a gap therebetweenwhich extends circumferentially around said body wall, said methodcomprising: placing said drum on a supporting platform at an operatorstation in spaced relationship with respect to a tapered centeringmember having a first portion with an external diameter smaller than theinternal diameter of the first flange of said closure and a secondportion with an external diameter larger than the internal diameter ofthe first flange of said closure; effecting relative movement betweensaid platform and said centering member to cause said centering memberto engage within said closure and center said drum at said operatorstation and to place said drum in a location where said closure isreadily visible; rotating said drum about the axis of said body wall;forcing a wedging tool into a flange folding position between the outersurface of said body wall and the third flange of said closure;retaining said wedging tool in said flange folding position duringrotation of said drum to fold the second and third flanges of theclosure and the body flange to a position at an acute angle with respectto said body wall; moving a cutting tool relative to said drum into aflange severing position in engagement with the portion of said closurebridgiNg said second and third flanges; progressively moving saidcutting tool relative to said bridging portion under manual controlduring rotation of said drum while observing said closure to cause saidcutting tool to enter the gap between said body flange and bridgingportion to thereby sever said third flanges from said closure while saidbody flange remains completely intact; effecting relative movementbetween said platform means and said centering member and removing saiddrum from said operator station; removing said closure from said one endof said body wall to provide access to the interior thereof; treatingthe interior of said drum; placing a new closure on the open end of saidbody wall; and folding first, second and third flanges on said newclosure into the previously described sealed relationship with said bodywall and flange thereof to thereby provide a reconditioned drum havingthe same height and volumetric capacity as the original drum and whichis itself capable of being further reconditioned.
 8. A method as setforth in claim 7 wherein relative movement between said platform andsaid centering member is effected by moving said platform relative tosaid centering member.
 9. A method as set forth in claim 8 wherein saidcentering member is positioned above said platform, and wherein saidplatform is moved vertically relative to said centering member.
 10. Amethod as set forth in claim 9 wherein said drum rotating step isperformed by rotating said centering member while said drum is heldthereagainst by said platform.